Oil cleaner



Patented Sept. 5, 1944 OIL CLEANER William H. Manning, Birmingham, and Clarence F. Smart, Pontiac, Mich., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application August 20, 1940, Serial No. 354,054

(Cl. .E-170) 8 Claims.

been found that it would require too large a filter to enable all of the oil to be iiltered. Where a screen iilter is used, a screen of mesh ne enough to be eiiicient would plug quickly and shut off the entire oil supply. The desideratum has been to build in, as a part of the engine lubricating system, some kind of an apparatus which would pass all of the oil therethrough before it is delivered to the engine bearings, and remove from the oil the deleterious contaminating matter such as small iron particles, grit, abrasives, etc. In our investigation of the purication of oil, we found that it was desirable to have a cleaner which had the following characteristics:

1. It should be located on the suction side of the oil pump so that all 4oil passes through the apparatus-before entering the bearings.

2. Particles harmful to the bearings must be very eiiiciently and quickly removed-from double to triple the veiectiveness of oil lters now in use.

3. The apparatus must maintain its efficiency for the life of the engine.

4. At any operating engine .temperature and with any of the usual grades of oil recommended for automobile engines, the .apparatus must perform eifectlvely.

5. The apparatus must not need cleaning and there should be no auxiliary apparatus or tment to buy.

6. It must be built-in so that there is no possibility of the oil tubes leaking or being damaged, resulting in loss of oil.

With a view to-obtaining the six characteristicsmentioned in the-foregoing, we made experiments with a type of oil cleaner which separated particles `from the oil by means of the combined kinetic energy ofthe contaminating particles plus the force'of gravity acting on them. This action will cause the particles to be precipitated and remove them from the system.

The cleaner which we have invented is placed l for use when oil is cold and consequently quite viscous, but it is useless when oil is hot because the cleaner will take out particles of a lneness which will go right through the screen and will consequently remove those particles which the screen would catch. The oil rst passes a screen which removes from the oil any large or heavy particles. The oil then passes up a riser and is caused to impact-or rush against an oil ow reversing element. This element has a rounded or bowl-shapedsurface With a rounded cone at the middle thereof, and the reverser causes the oil not only to change in direction of ilow, but to flow over the outside of the riser. The riser is mounted in a cup which acts as a sediment trap and immediately below the top of the riser a baille plate is mounted and against this baffle the oil strikes as it comes from the oil reversing member. The oil, as it strikes the' baille, enters a greatly enlarged passage so that the speed of the iiow of the oil is considerably decreased and at the place` where the oil strikes the baiiie the contaminating particles in the oil are separated and leave the oil, pass outwardly along the baille surface and drop to the sediment chamber below the baffle.- The oil in the sediment ,chamber below the baiile remains substantially in an undisturbed condition so that any sediment once reaching the sediment trap is permanently removed from the system.

From the baille the oil passes upwardly because the baille again changes the direction of flow. In its upward direction it passies into a chamber or annular channel'in a closure or cover for the sediment trap and from this chamber the oil passes through a pipe to the pump and is then delivered to the bearings.

On the drawing Figure 1 is a transverse sectional view through the lower pari'. of an internal combustion engine and the oil pan thereof, showing the installation of the oil cleaner, parts of the cleaner being broken away better to illustrate the construction.

Figure 2 is a view similar to Figure 1 on'a larger scale showing a section through the oil cleaner.

Figures 3 `and 4 are partial sectional views on the lines 3-3 and 4-4 of Figure 2. f

Referring to the drawing, the numeral 2 indicates an internal combustion engine as a whole. The engine has the crankcase 4 and the oil pan 6 secured to the crankcase by means of the machine bolts 8. The oil pan 6 has the usual drain opening closed byl a plug 9. The crankcase has a bearing opening I0 in which there is mounted the bearing sleeve I2 of the shaft I4 which drives an oil pump I6 of the usual type. The shaft I4 receives its power either from the crankshaft or camshaft (not shown) of the engine. 'I'he pump I6 has the removable cover I8 to enable the inspection of the pump. One of the stationary bearing caps of the crankshaft is indicated at 26. At the underside of the crankcase, a transverse arm or brace 22 is secured by means of the machine bolts 23, and to this transverse brace the cil cleaner 24 of the invention is secured by means of a plurality of machine bolts 26.

` Referring to Figure 2, the oil cleaner 24 comprises in general the cover or closure 28, the

outer shield 36, the screen assembly 32, spaced from the shield 30, and the cup assembly 34 inside and spaced from the screen assembly 32. The shield forms the outer protecting member of the oil cleaner and is secured to the cover 28 by means, of a plurality of machine bolts 36 passing through the end flange of the cover 28 and through suitable openings in-=a ange.38 formed at the top of the shield. A ring 40 provided with threaded openings and positioned below the flange 38 holds the parts in place and suitable gaskets 42 are used to form a fluid tight connection. The lower part. of the shield 30 is outwardly bent as at 44 and downwardly anged as at 46 to form an annular shoulder.

The cup assembly 34 has the upper flange 48 which is positioned under the flange 38 of the cup and is held in place by means of the same machine bolts 36 and ring 40 which hold the flange 38. The cup itself is indicated at 50 and the bottom thereof, or the sediment trap, at 52. The bottom has an inwardly turned column or inlet 54 and to. the column a tubular riser 56 is rigidly secured. The riser 56 or flow directing member has secured thereto below its top a baille 58 having a ange 60 which ts tightly against the upper part of the riser and is rigidly secured thereto. The battle 58 terminates short of the inner edge of the cup 50 as -indicated at 62, and is also provided with three narrow legs 64 which extend out to the inner edge of the cup and are rigidly secured thereto.

The screen assembly 32 comprises the lower substantially flat screen element 66, the spiderlike support therefor 65, the upstanding* cylindrical screen 68, 4and the outer supporting and lretaining ring 10. These pa :ts are flanged and secured together as best shown at 12, and the ring 10 is provided with a plurality of extensions or feet 14 which fit under and against the shoulder formed by parts and 46. Between the feet 14 the space indicated at I6 is open to enable the oil to pass therethrough to the cylindrical screen 68. The spider 65 has formed thereon adjacent its center three Z-shaped feet 18 which project upwardly and fit against the bottom 52 of the cup 50 and act as spacers.

The cap or closure 28 has formed therein at the centery thereof the ilow reversing construction or member 80 which has the conical projection 82 at the middle thereof. This projection 82. is rounded and smooth and extends downwardly and in line with the center line of the tubular riser 56. The ilow reversing surface 84 of the reversing element 80 is rounded and smooth and vof inverted bowl shape and in cross section appears arcuate as is shown in Figure 2. Below the top of the riser 56 the sides of the reverser 88 are straight to form a tubular neck as indicated at 86 and this neck extends downwardly a substantial distance beyond the top of the riser 56, In

practice it has' been found desirable to make the cross-sectional area of the inside of the riser -56 substantially the same as the cross-sectional area between the outer part of the riser and the inside of the neck 86 so that no change in the speed of flow of oil will take place when the oil Referring to Figures 2 and 3, there is shown the manner in which the screen assembly 32 is secured to the shield or shroud 3 0. The ange 46 is provided with a plurality of openings 84 and 96 in which there are received the bent intermediate part 98 and the ends |00 of a spring wire. The body of the wire rests against the edges |02 o'f the feet 14 removably to hold the screen assembly inside the shield and between the shield and cup 50 as is shown in Figure 2. To remove the screen assembly the ends |00 are pulled toward each other 4to remove them from the openings 96. The wire may then be removed from the underside of the cleaner.

In the operation of the device the pump I6 will draw the oil from the oil pan 6 through the bottom screen 66 and also up through theopenings I6 to the screen 68. The oil will pass through the screens and ilow to the underside of the cup 50, and enter the column 54 and ow up the riser 56. At the top of the riser 56 the oil will strike l the smooth surface of the flow reversing element and the contact with this smooth rounded surface will changethe direction of flow of the oil, that is, the ilow direction will be reversed but the speed of the' oil remains substantially the same as it was when it came up the riser, due to the fact that the area between the neck 86 and the top of the riser is substantially the same as the internal area of the riser. When the oil leaves the bottom of the neck 86 it will strike against the baille 58 but as will be seen fromv Figure 2, the area of the passage or conduit through which the oil flows is now very much increased (about ve times) so that the velocity of the flow of oil will be very much reduced. It is at this point, where the oil strikes the baille 58, that the contaminating particles such as pieces of metal, grit, abrasives, etc., are thrown out, apparently due to the kinetic energy of the particles and due tothe pull of gravity. These particles will move to the edge 62 of the baiile and then slowly work their way to the bottom 52 of the sediment trap. When the oil strikes the baiiie 58 the flow is again reversed and the cleaned oil will now iiow or be drawn upward into the chamber in the closure 28. From the chamber 88 the oil will be drawn through the pipe 82 to the pump I6 and Passed to the bearings. The cross-sectional area of the pipe 92 is considerably less than the cross-sec-l tional area of the riser. The velocity through the Pipe 82 is about fiveA times that through the riser 56.

. From the description as given, it is to be seen that the conduit or path of ilow of the oil through the cleaner is a circuitous one. The flow of oil 4 is fromthe oil pan 6, through the screens 66 and 'Iiil 88, to the underside of the cup 50, up the riser 56, thenreversed by the member 80, then down- Ward against the baille-58 which reverses the flow to an upward direction and into the chamber 88 from which it is withdrawn by the pump.

In actualpractice it has been found that a cleaner such as shown in the drawing need not be replaced for the life of the engine; in other words, the -cleaner will continue to function substantially indefinitely. Actual tests have shown that the oil at the bottom 52 of the sediment trap will remain substantially motionless and that any particle that has once dropped over the edge 62 of the bailie will be permanently removed from the system. Our experiments have also shown that a single passage through the cleaner is ample to remove all of the particles which have a harmful effect on the bearings of the engine. Some particles, such as small, light pieces of carbon, may pass to the bearings, but these parts are not deleterious and in time even the carbon particles will be removed. The cleaner does not plug or become clogged for the reason that the space in the sediment chamber at the bottom of the cup 50 is large enough to take care of the removal of all impurities for the life of the engine. The cleaner therefore never plugs or clogs.

Our investigations have also shown that the cleaner is effective with any type of oil, but works better with a thin oil or a hot oil, so that the cleaner4 is more effective after the' oil in thev crankcase has been heated.

An additional advantage of the cleaner is that it is permanently built in as a part of the lubricating system and installed in the crankcase where it is out of the way and never needs to be replaced. It is also out oi' the way in so far as possible damage is concerned.

In our experiments we found that there is a definite relationship between the efficiency of the filter and tho distance below the bottom of the neck 86 at which. the baiile 58 must be placed and this position must be found by experiment and trial. For a normal cleaner, such as is installed in the lubricating system of an internal combustion engine' as used on an automotive vehicle, it has been found that a riser having a diameter of substantially 1 should project up into the neck 86 of flow reversing member 80 a distance of about In other words, the neck 88 should extend below the top of the riser a distance of about and the distance from the tip of the cone 82 to the plane of the top of the riser should be substantially 11;". With dimensions las given, the baille 58 should be placed subportant that the ow area be greatly'increased.

By referring to Figure 2, it willv be noted that as the oil is directed against the bailie58, the area of flow is many times greater than the cross sectional area between-the neck 88 and the top of the riser 56. This will cause a very material stance, at an oil ow of 0.5 gallon a minute, at a temperature of 250 F., the efliciency is about 88% and as the oil flow increases with the speed of the engine` there will be av decrease in efficiency to about `'78% for an oil ow of 2.5 gallons per minute. It is therefore to be Aseen that the minimum eiiiciency of the present type oil cleaner is a number of times better than the maximum efliciency of a filter element through which but a fraction of oil passes. y In connection with the efficiency of the cleaner and in order to make the data givenI in the foregoing description accurate, three items must be given consideration:

1. The velocity of the oil through the cleaner.

2. The oil temperature and the grade of the oil, which is equivalent to specifying the viscosity.

3. The size of the particles removed.

The principal advantages of the cleaner are:

1. All oil passes through` cleaner before reaching any movingpart.

2. `Cleaner contains no iiltering material-#only space for cleaning action and'collected material.

3. Because thev cleaner contains no filtering material, the possibility of element break-down- .service adjustment.

5. The cleaner removes onlygthose particles injurious to bearing surfaces.

6. The efficiency of the cleaner is not decreased by the collection of undesirable material.

7. Under conditions of high temperature operation, the cleaner efilciency is maximum; it therefore operates best where the need for oil cleaningr is greatest; in the high temperature sections of the country.

8.- The cleaners efficiency under operating conditions is suflcient to very materially prolong the useful life of all moving parts in an engine, par-f ticularly those to which oil is fed under pressure.

We claim:

1. In an oil cleaner, a ilow directing member in the cleaner, means to draw the oil to be cleaned through the flow directing member, a flow reversing element having a rounded reversing surface, said element being positioned immediately above but spaced from the end of the flow `directing'member and in the path of flow of the oil to cause a reversal oi' direction of flow by impact slowing up in the velocity of the oil and enable v the particles to be thrown out by the baiil'e and find their way over the edge 82 to work their way 'by gravity into the bottom 52 -of the sediment trap.

lThe best modern filtering element decreases in efliciency in proportion to the age of the filter, and this emciency is, finally zero when the filter is plugged. With the present oil cleaner, the emciency at the start is between 80% and 90%. and does not decrease throughout the life of the cleaner. The actual cleaning efficiency of the novel cleaner varies slightly with the speed of the engine and the viscosity of the oil. For inof the. oil thereagainst, a at baille beyond the flow reversing elementV and being positioned around the flow directing member and having its outer edge spaced from the inside of the cleaner,

said baille causing the precipitation of the impuritiesvin the oil and causing the oil againto reverse the direction of its flow, a sediment trap below said baille to receive and retain the impurities precipitated at the bafile, the space in the cleaner through which the oil flows being greatly increased after the oil passes the baille, and outlet means beyond the baiile to enable lthe oil f to pass to the first named means.

2. In an oil cleaner, a flow directing member. a flow reversing element having a curved reversing surface spaced in xed position above the ow directing member and in the path of flow therefrom to cause flow in a reverse direction, a baille around said now directing member so spaced from said flow reversing element as to cause immediate radial ilow outward from said reversing element at 'a reduced velocity along said baille to its periphery; a container surrounding and extending above' and below said baille and spaced therefrom, an outlet from said container above said baiie, and means for causing continuous orw of oil through said container.

3. In a cleaner for liquids, a cylindrical container, an inlet conduit in said container, a member for directing downward annular ilow coaxial with said inlet conduit, and so spaced therefrom as to form a passage of undiminishing cross section between said member-and said conduit. an annular baille coaxial with said conduit and spaced below said member at such distance as will aiiord a radial path of flow of undiminished cross section between said member and said baille, the wall of said container being spaced from and extending below said baille, an outlet :for said container above said bailie, and means for producing continuous flow of liquid through said container.

4. In a cleaner for liquids, a container, an in- .let conduit for producing an upward ow of liquid in said container, a flow reversing member in fixed position coaxial with said inlet conduit and so spaced therefrom as to afford a pasmember at such distance as will aiord a radial path of flow of undiminished cross section between said member and said baille, the wall of said container being spaced from and extending below said bafile, an outlet for said container above said baffle, and means for producing continuous iiow of liquid through said container.

5. In a cleaner for liquids, a container, an inlet conduit in said container, a member for directing downward annular flow coaxial with said conduit, a bafe, said bale and said container being so spacedas to produce unidirectional ow of continually decreasing velocity towards the edge of said baiile, the wall of said container beduit, said baiile beingso positioned in said con- .tainer as to cause unidirectional radial ow of continually decreasing velocity along the upper surface of said baille to its periphery, the wall of said container, being spaced from and extending below said baille, a second conduit leading from said container above said baille, and means for producing a flow of liquid through saidl cleaner.

' 7. In a cleaner for liquids, a container, a conduit in said container for directing upward flow, a ow reversingv member so spaced from said conduit as to afford a passage of undiminishing cross section between said member and said conduit, a baille normal to the iiow of said reversing member so spaced therefrom as to afford radial flow of continually decreasing velocity towards 'Y the edge of said baffle, said edges being spaced from the wall of said container at a distance above the bottom thereof, and means for producing a iiow of liquid through said cleaner.

8. A device for separating solids from a liquid comprising a casing having a cylindrical wall, an inlet opening and an outlet opening, an inlet pipe extending from said inlet opening and standing vertically in said casing, a bonnet fixed in said casing above the upper open end of said inlet pipe for reversing theflow of liquid 4Ilowing therefrom, and a dispensing flange fixedv around said inlet pipe and extending outward nearly to, but clear from said cylindrical wall.

W'ILLIAM H. MANNING. CLARENCE F. SMART. 

